To meet customer demand, image output devices such as a printer or display need to produce a consistent spectrum of colors over time. Customers want a printing system to produce a particular colored document consistently from day to day, or from job to job. To control the color rendering consistency of a printing device, the printing device is typically characterized and calibrated prior to being shipped to a customer. The characterization and calibration process produces a set of LUTs (look-up tables) which correlate a standardized set of target colors with the appropriate device dependent color space values necessary to produce the target colors with the printing device. Characterization and calibration is generally referred to as profiling a device or printer. To accomplish profiling of a printing device, a spectrophotometer or other image sensing device is used to measure the colorimetric properties of the produced images. These measured colorimetric properties provide an objective basis of comparison to the reference target color set and provide the necessary feedback to iteratively generate accurate device dependent LUTs. Stated another way, device dependent CMYK values for one device can be correlated to the reference target color set, and this reference target color set can be correlated to the device dependent CMYK values for another device so that a LUT can be constructed relating the device dependent CMYK values for the first device to the device dependent CMYK values for the second device. Device profiling can also be applied to a display where an image sensing device is approximately located to the display for colorimetric measurements of the displayed image. In addition, multiple LUTs may be generated for an image output device to account for multiple media types and/or half tone screens.
In a cascaded color management strategy, a fleet profile that represents a typical printer and having many profiling strategies incorporated with appropriate GCR converts the images to a set of typical CMYK. The engine takes this set of typical CMYK and converts to its own device cmyk for printing. Advantages of a cascade strategy are that it can have one DFE with the fleet profile to drive a set of engines so that cost will be lower and it has a clean separation between the DFE and the engine so that development of the DFE and the engine color management system can be separated. In the cascade strategy, many elements of color management are handled inside the fleet profile that resides in the DFE, while the variation of the individual engine is handled by a multi-dimensional LUT that transforms from the fleet CMYK to the engine cmyk for printing and that resides inside the engine. A unique requirement from this strategy is to construct the LUT that preserves the color management strategy of the fleet profile in the DFE. When the engine changes due to drifting or component replacing, the LUT has to be updated.
Accordingly, what is needed in this art are increasingly sophisticated systems and methods for generating (creating/updating) a fleet CMYK to engine cmyk lookup table (LUT).